TUCSON,CapitalVault Ariz. (AP) — A federal grand jury in southern Arizona has indicted a Tucson man and woman in an alleged conspiracy to embezzle millions of dollars from a nonprofit, federally funded tribal health care organization.

The indictment unsealed on Monday alleges that Kevin McKenzie, the chief operating officer of Apache Behavior Health Services, embezzled millions from the organization that was formed under the laws of the White Mountain Apache Tribe.

Prosecutors believe McKenzie, 47, used another organization created to help Apache youth to funnel some $15 million to himself through a backdoor financial scheme. Also named in the 40-count indictment was Corina L. Martinez, 41, the sister of McKenzie’s longtime domestic partner.

In addition to conspiracy to embezzle and embezzlement, the counts include wire fraud and conspiracy to commit money laundering.

Defense attorney Louis Fidel said in a statement that McKenzie “strongly denies the allegations against him, and we intend to vigorously defend the case.” He said McKenzie’s work on the reservation over the years had benefited many tribal members who previously were underserved.

Martinez “has spent many years providing behavioral health services to those in need,” her attorney Joshua Hamilton said in a separate statement. “We will vigorously defend Ms. Martinez in this matter and protect her reputation in the behavioral health community.”

Office phones at the White Mountain Apache Tribe rang unanswered on Friday.

Arraignment in U.S. District Court in Tucson was set on Jan. 5 for Martinez and on Jan. 12 for McKenzie.

The case appears unrelated to widespread Medicaid scams have bilked the state of Arizona out of hundreds of millions of federal dollars. Thousands of Native Americans who traveled from reservations and even other states to seek help for alcohol and drug addictions at Phoenix area rehabilitation facilities have often been left homeless by the billing schemes.

In those cases, fraudulent charges for reimbursement were submitted mostly through the American Indian Health Program, a Medicaid health plan that allows providers to bill directly for reimbursement of services rendered to Native Americans and Alaska Natives.